The answer to this question is <span>confounding variables.
</span><span>confounding variables Refers to the type of variables that researchers couldn't control (such as genetical anomally or natural disasters)
</span>The existence of this type of variables will damage the validity of the experiment results and make it untrustworthy.
Because <span>people have always produced food in distinctive ways in different regions.
Different regions will have different climate and land composition that could make humans unable to produce a certain type of crops.
But despite this limitation, humans always managed to adapt and find the type of food crops that are possible to be planted in their region.</span>
Answer:
the correct answer is the guards
The Tuscarora Indiana was originally lived in North Carolina. The 1700s, they were killed and used as slaved by the British during the war. Most of the survivors moved to New York to move with their relatives.